1. Field of the Invention
The invention relates to a pneumatic tool, and more particularly to a handle body for a pneumatic tool.
2. Description of the Related Art
Referring to FIG. 1, a conventional pneumatic tool 1 includes a front handle section 11 and an output unit 12. The front handle section 11 has an axial hole 111 extending along a central axis (X), a through hole 112 formed through the front handle section 11 along a direction perpendicular to the central axis (X), and a generally U-shaped opening 113 formed in a front end of the front handle section 11. A driving unit (not shown) is mounted into the axial hole 111 through the opening 113. The output unit 12 is mounted into the through hole 112 through the opening 113.
However, since the output unit 12 mounted within the through hole 112 applies a pressure to a wall of the front handle section 11 defining the opening 112 in a direction perpendicular to the central axis (X), if the front handle section 11 is rotated during work operation, the opening 113 may become larger, thereby shortening the service life of the pneumatic tool 1 and reducing the structural stability of the pneumatic tool 1.
FIG. 2 shows a pneumatic ratchet drive wrench disclosed in U.S. Pat. No. 6,578,643. The pneumatic ratchet drive wrench includes a front handle section 21, an output unit 22, a driving unit 23, and a cover plate 24. The front handle section 21 is formed with a chamber 211 that is opened downwardly. The output unit 22 is disposed within the chamber 211, and has a driving head 221 extending along a vertical axis (Z). The driving unit 23 is also disposed within the chamber 211 for driving the output unit 22. The cover plate 24 is secured to a bottom surface of the front handle section 21 for covering the chamber 211, and has a through hole 241 permitting the driving head 221 to extend therethrough.
Although the front handle section 21 is not formed with a U-shaped opening, it is necessary to form a plurality of fastener holes 242 in the cover plate 24 to allow the cover plate 24 to be secured to the front handle section 21 by lock bolts . As such, high precision is required for forming the through hole 241 and the fastener holes 242 in the cover plate 24. Furthermore, in such a configuration, at least one partition needs be disposed in the front handle section 21 for forming at least two irregular-shaped chambers to position rotating and moving components within the front handle section 21, thereby resulting in difficulties in manufacturing and assembling the pneumatic ratchet drive wrench.